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Watch Antares Disappear on Saturday Night

The Moon will be only about 16 hours from full when, on Saturday evening June 6th in the Americas, it will cross the 1st-magnitude red supergiant star Antares.

Tony Flanders

The occultation will be visible across much of the United States and Canada, all of Central America and the Caribbean, and northern South America. Surrounding areas get a still-spectacular near miss.

In a telescope, you’ll see the round Moon’s most shadow-marked rim creep up to fire-colored Antares. The star will blink out behind the invisible dark limb just before it reaches the brightly sunlit lunar mountains and plains. Antares has such a large angular size for a star (40 milliarcseconds) that, seen from locations where it grazes the Moon’s edge, it may appear to fade down for a second or less rather than snapping out instantly.

In North America, Antares disappears some time between 9:40 and 11:20 p.m. EDT, depending on your location. See the IOTA website for a timetable with local details.

Antares will reappear up to an hour or more later from behind the sharper bright limb, with the Moon now higher in the southeastern sky.

Antares and Aldebaran are the only strongly reddish stars that are near enough to the ecliptic, and bright enough, ever to be seen well on the Moon’s bright limb. For these rare few seconds, to me they look like a fire on the Moon.

7 thoughts on “Watch Antares Disappear on Saturday Night”

The diagram of the occultation path in this article has irregular areas on both the eastern and the western ends of the path. If I’m picturing this right in my head, in the eastern area Antares can be seen disappearing behind the Moon, but both will have set below the horizon when Antares reappears; while in the western area Antares will be occulted by the Moon at Moonrise, and the reappearance will be visible. Is this correct?

In any event, it looks like San Francisco will miss this occultation completely, and it’s been cloudy here anyway.

>>> in the eastern oval Antares can be seen disappearing behind the Moon, but both will have set below the horizon when Antares reappears; while in the western oval Antares will be occulted by the Moon at Moonrise, and the reappearance will be visible. < <<
That is correct.

It was not a grazing occultation from my neck of the woods but I did observe the event from the Astronomical Society of Harrisburg’s Naylor Observatory using a 17″ f/15 classical Cassegrain at 162x and its 5″ f/5 finder scope. I took some DSLR photos of the Moon and Antares after Antares reappeared. Even though the conditions weren’t ideal, I was able to catch a glimpse or two of Antares B too.

I caught the Occulation and Reappearance of Antares last night with my 11 x 80 binoculars. I was a little surprised to see Antares appear so bright as it was close to the limb of Luna, 10 minutes before disappearance. The Moon’s ray system was outstanding in the binos with Antares sitting just above the small greyish crater of Plato. It was easy to follow the star flickering until it snuffed out behind the limb of Luna. Ditto for the reappearance. location was Bar Beach, Manhasset-Long Island.

I observed the occulation of Antares from Waipahu, Hawaii (15 miles west of Honolulu) on July 3 between 11:58 and 11:59 PM local time (GMT = 10). Staying up to view the re-emergence at 1:18 AM July 4 — hopefully the clouds stay away. Only had 8X40 binoculars through clouds so I couldn’t see Paul Voto’s degree of detail!

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